Two loads can be supplied from separate converters which are arranged to work in offset phase relation to each other. The phase displacement reduces the alternating component in the current drawn from the source. However, a strong alternating component occurs in the load current of each motor, and in order to avoid commutating and other drawbacks, this component must be held down by giving the load circuit a high inductance, for example, by smoothing inductors connected in series with the load. These inductors, which in practice it has been found, must often be of large dimensions resulting in considerable disadvantages.
It is further known to connect, in parallel, several loads, for example vehicle motors, with each other so that they form one single load. This load is connected to the mutually parallel-connected phase-displaced converters. With this connection, the phase displacement between the converters achieves a substantial reduction of the alternating component in the load current compared with the connection mentioned in the introduction at the same size of the smoothing inductors, that is, it will be possible in practice to work with considerably smaller smoothing inductors. In many different types of loads, for example, separately excited vehicle motors, this connection will lead to an uncontrolled and unacceptably uneven division of current between the loads, and in practice it will be necessary to arrange complicated regulating systems to achieve a uniform distribution of the load current between the loads.